The constant folding for sdiv and udiv has a big discrepancy between the
comments and the code, which looks like a typo. Currently, we're folding
X / undef pretty inconsistently:
0 / undef -> undef
C / undef -> 0
undef / undef -> 0
Whereas the comments state we do X / undef -> undef. The logic that
returns zero is actually commented as doing undef / X -> 0, despite that
the LHS isn't undef in many of the cases that hit it.
llvm-svn: 261813
Summary:
GEPOperator: provide getResultElementType alongside getSourceElementType.
This is made possible by adding a result element type field to GetElementPtrConstantExpr, which GetElementPtrInst already has.
GEP: replace get(Pointer)ElementType uses with get{Source,Result}ElementType.
Reviewers: mjacob, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16275
llvm-svn: 258145
Make sure to check that the destination type is sized.
A check was present but was incorrectly checking the source type
instead.
Patch by Amaury SECHET!
Differential Revision: http://reviews.llvm.org/D15264
llvm-svn: 255536
Because mod is always exact, this function should have never taken a rounding mode argument. The actual implementation still has issues, which I'll look at resolving in a subsequent patch.
llvm-svn: 248195
Summary: This fixes a variety of typos in docs, code and headers.
Subscribers: jholewinski, sanjoy, arsenm, llvm-commits
Differential Revision: http://reviews.llvm.org/D12626
llvm-svn: 247495
David Majnemer (the original author) believes this to be an impossible
condition to reach anyway, and no test cases cover this so we'll go with
that.
llvm-svn: 245712
In the glorious future of opaque pointer types, it won't be possible to
retrieve the pointee type of a pointer type which is what's being done
in this GEP loop - but the first iteration is always a pointer type and
the loop doesn't care about that case, except whether or not the index
is a constant.
So pull that special case out before the loop and start at the second
iteration (index 1) instead.
Originally committed in r236670 and reverted with a test case in
r239015. This change keeps the test case working while also avoiding
depending on pointee types.
llvm-svn: 239629
Clang regressions were caused by more stringent assertion checking
introduced by this change. Small fix needed to clang has been committed
in r236751.
llvm-svn: 236752
Summary:
This patch adds constant folding of insertelement instruction to undef value when index operand is constant and is not less than vector size or is undef.
InstCombine does not support this case, but I'm happy to add it there also if this change is accepted.
Test Plan: Unittests and regression tests for ConstProp pass.
Reviewers: majnemer
Reviewed By: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9287
llvm-svn: 235854
Summary: Constant folding of extractelement with out-of-bound index produces undef also for indexes bigger than 64bit (instead of crash assert failure as before)
Test Plan: Unit tests included.
Reviewers: majnemer
Reviewed By: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9225
llvm-svn: 235700
Require the pointee type to be passed explicitly and assert that it is
correct. For now it's possible to pass nullptr here (and I've done so in
a few places in this patch) but eventually that will be disallowed once
all clients have been updated or removed. It'll be a long road to get
all the way there... but if you have the cahnce to update your callers
to pass the type explicitly without depending on a pointer's element
type, that would be a good thing to do soon and a necessary thing to do
eventually.
llvm-svn: 233938
This pushes the use of PointerType::getElementType up into several
callers - I'll essentially just have to keep pushing that up the stack
until I can eliminate every call to it...
llvm-svn: 233604
PPC_FP128 is really the sum of two consecutive doubles, where the first double
is always stored first in memory, regardless of the target endianness. The
memory layout of i128, however, depends on the target endianness, and so we
can't fold this without target endianness information. As a result, we must not
do this folding in lib/IR/ConstantFold.cpp (it could be done instead in
Analysis/ConstantFolding.cpp, but that's not done now).
Fixes PR23026.
llvm-svn: 233481
Constant folding for shift IR instructions ignores all bits above 32 of
second argument (shift amount).
Because of that, some undef results are not recognized and APInt can
raise an assert failure if second argument has more than 64 bits.
Patch by Paweł Bylica!
Differential Revision: http://reviews.llvm.org/D7701
llvm-svn: 232176
Summary:
See the two test cases.
; Can fold fcmp with undef on one side by choosing NaN for the undef
; Can fold fcmp with undef on both side
; fcmp u_pred undef, undef -> true
; fcmp o_pred undef, undef -> false
; because whatever you choose for the first undef
; you can choose NaN for the other undef
Reviewers: hfinkel, chandlerc, majnemer
Reviewed By: majnemer
Subscribers: majnemer, llvm-commits
Differential Revision: http://reviews.llvm.org/D7617
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231626
Consider:
void f() {}
void __attribute__((weak)) g() {}
bool b = &f != &g;
It's possble for g to resolve to f if --defsym=g=f is passed on to the
linker.
llvm-svn: 223585
The LLVM Lang Ref states for signed/unsigned int to float conversions:
"If the value cannot fit in the floating point value, the results are undefined."
And for FP to signed/unsigned int:
"If the value cannot fit in ty2, the results are undefined."
This matches the C definitions.
The existing behavior pins to infinity or a max int value, but that may just
lead to more confusion as seen in:
http://llvm.org/bugs/show_bug.cgi?id=21130
Returning undef will hopefully lead to a less silent failure.
Differential Revision: http://reviews.llvm.org/D5603
llvm-svn: 219542
Global variables that have `extern_weak` linkage may be null, so it's
incorrect to add `inbounds` when constant folding.
This also fixes a bug when parsing global aliases, whose forward
reference placeholders are global variables with `extern_weak` linkage.
If GEPs to these aliases are encountered before the alias itself, the
GEPs would incorrectly gain the `inbounds` keyword as well.
llvm-svn: 215803
A GEP of a non-weak global variable will not be equivalent to another
non-weak global variable or a GEP of such a variable.
Differential Revision: http://reviews.llvm.org/D4238
llvm-svn: 212360
As a follow-up to r210375 which canonicalizes addrspacecast
instructions, this patch canonicalizes addrspacecast constant
expressions.
Given clang uses ConstantExpr::getAddrSpaceCast to emit addrspacecast
cosntant expressions, this patch is also a step towards having the
frontend emit canonicalized addrspacecasts.
Piggyback a minor refactor in InstCombineCasts.cpp
Update three affected tests in addrspacecast-alias.ll,
access-non-generic.ll and constant-fold-gep.ll and added one new test in
constant-fold-address-space-pointer.ll
llvm-svn: 211004
name might indicate, it is an iterator over the types in an instruction
in the IR.... You see where this is going.
Another step of modularizing the support library.
llvm-svn: 202815
Justin Bogner